Overview

Glaucoma is the second most common cause of blindness in the UK. It affects around 2 in every 100 people over the age of 40. 

The NHS website has more information about glaucoma.

About open angle glaucoma

Open angle glaucoma is a condition where there is progressive damage to the optic nerve, which is the nerve that supplies your vision. If it's not treated, it can lead to blindness.

Usually, the edges of your vision (peripheral vision) are affected first. Over time, if the glaucoma is not treated, it can also affect your central vision. Both eyes are usually affected, although it may be worse in 1 eye.

It's not possible to reverse any damage that has already happened to the optic nerve. This is why it's important for open angle glaucoma to be found as early as possible.

As you get older, there is a natural deterioration of the optic nerve. If you have glaucoma, this happens at a faster rate.

Types of open angle glaucoma

There are different types of open angle glaucoma.

• Primary open angle glaucoma. This is the most common type, where there is chronic (long-term) high pressure in the eye.
• Normal tension glaucoma. This type causes damage even when the eye pressure is normal. 
• Secondary glaucoma. This happens when high eye pressure is caused by trauma, medicines or other eye conditions.
• Congenital (juvenile) glaucoma. This is when a baby is born with glaucoma or develops it in childhood.

Causes of open angle glaucoma

The exact cause is usually unknown.

It has not been shown to be linked to specific lifestyle choices.

One of the main risk factors is increased pressure inside the eye, caused by a build-up of fluid.

Glaucoma is more common in older adults and often develops slowly over time.

You may also be more likely to develop glaucoma if you:

• have a family history of glaucoma
• are of Afro-Caribbean background
• have myopia (short-sightedness) 
• use steroid treatment, including eye drops, inhalers, creams and tablets

Signs and symptoms

In the early stages, glaucoma usually causes no noticeable symptoms or vision loss. 

As the condition progresses, you may start to notice loss of vision around the edges of your vision. Because this usually happens gradually, it's often not noticed until the condition is more advanced.

Eventually, your central vision can also be affected. Without treatment, this can lead to blindness. 

Diagnosis

There are different tests that can be done to diagnose open angle glaucoma. 

Optic nerve assessment

The optic nerve at the back of the eye is carefully examined. A scan called optical coherence tomography (OCT) may be used to look at the nerve in more detail.

Field of vision test

This computerised test checks your field of vision and shows whether there are any areas where vision is reduced or missing.

Eye pressure test

Your eye pressure is measured using a device called a tonometer. Your eye is numbed, and a yellow dye is used. The test is quick and not painful.

Treatment

All of these treatments aim to lower the pressure inside your eye.

Eye drops

Eye drops work by increasing the amount of fluid leaving your eye or by reducing the amount of fluid being produced.

You need to use your eye drops every day to help control your eye pressure.

Laser treatment

Laser treatment may be offered if your eye is suitable. It is used to help improve how well fluid drains out of your eye.

Surgery

Surgery is usually considered if other treatments are unsuccessful or not suitable for controlling your eye pressure.

If you do not have treatment

If you do not have treatment, your eye condition will continue to get worse, and so will your sight. Over time, this can lead to permanent blindness.  

What you can do to help yourself

Driving and glaucoma

Because open angle glaucoma can affect your peripheral vision, it may affect your ability to drive safely.

If it affects the vision in both of your eyes, you should notify the DVLA. They will assess whether you can continue to drive safely. Your clinician can advise you on whether you need to notify the DVLA.

Support and more information

The NHS has more information about glaucoma. 

Glaucoma UK 

https://glaucoma.uk

Royal National Institute for the Blind (RNIB)

www.rnib.org.uk